Adapter for converting low pressure pilot burner for use with high pressure gas supply

ABSTRACT

An adapter for converting a standard low pressure pilot burner for use with a high pressure gas supply including a fitting adapted to engage tubing for supplying the gas under high pressure and an orifice member of the pilot burner, the fitting carrying a pair of pressure reducing orifices interconnected by an elongated passage through the fitting.

United States Patent Mo is 1451 Nov. 13, 1973 1 ADAPTER FOR CONVERTINGLOW 9,396 11/1852 Wood 239/5903 PRESSURE PILOT BURNER FOR USE WITH z 5 22? i:

, a er HIGH PRESSURE GAS SUPPLY 522,088 6/1894 Shaw 239/5903 [75]Inventor; Louis P, Morris, Garden Grove, 917,998 4/1909 Buddington239/590.3 X

Calif.

[73] Assignee: Robertshaw Controls Company, Primary Henson wood 11Richmond, Assistant Examiner-John J. Love Filed A r 3 1972Attorney-Anthony A. OBrien 21 A l. N 240,55 1 pp 0 8 57 ABSTRACT [52 us.01 239/5903 239/590.5 239/596 adapter cnverting a Standard low Pressure51 Int. Cl .7 liosb 1/00' Pilt burner use with a high Pressure gassL'PPIY [58] Field of Search 239/590, 590.5, 590.3, duding a fittingadapted engage tubing Supply- 239/596 600 ing the gas under highpressure and an orifice member 4 of the pilot burner, the fittingcarrying a pair of pres- [56] References Cited sure reducing orificesinterconnected by an elongated f' UNITED STATES PATENTS passage throughthe ittmg 536,953 4/1895 Hughes et a]. 239/5903 15 Claims, 1 DrawingFigure BACKGROUND or THE INVENTION.

1. Field of the Invention The present invention'pertains to pilotburners and, more particularly, to a pilot burner adapted to permitutilization of pilot burners with gas supplied at high pressures.

2. Discussion of the Prior Art As is well known, many gas operatedappliances including a main burner normally utilize a pilot burner toprovide an ignition flame thereby rendering the burner continuously incondition for operation. Most gas supply lines utilized for suchappliances deliver-gas at low pressures, and standard pilot burners aredesigned, for operation with gas. supplied at such low pressures inorder to provide a pilot flame of predetermined size.

Recently, the number of gas appliances, being installed in multi-unitbuildings, sometimes referred to as high rise apartments or officebuildings, has substantially increased. It is desirable to utilize highpressure gas supplies for such buildings in order to provide adequateservice and to reduce construction costs; however, standard low pressurepilot burners cannot properly operate under such high pressureconditions. Thus, the problem exists in the gas appliance field ofhaving to vary construction of appliances, particularly pilot burners,dependent upon where the appliance is to be installed. z 7

At first glance, the above described problem appears to be of a simplenatur'eand easilysolved; however, attempts to construct an adapter topermit use of standard low pressure pilot burners with high pressure gassupplies have not met with success in that there are practicallimitations with respect to producing extremely small pressure reducingorifices, such adapter must preferably function foruse with non-candlingtab type standard pilotburners thereby preventing the use of extremelylong adapter passages, cost and complexity must be kept ata minimum, andinstallation must be facilitated in order to keep labor costs at' aminimum. SUMMARY OF THE INVENTION Accordingly, it is an object of thepresent invention to construct an adapter for use-with a standard lowpressure pilot burner-in order to convert such pilot burner for use witha high pressure gas supply.

The present invention is generally characterized in a pressure reducingadapter for converting a low pressure pilot burner for use with a highpressure gas supply, the pressure reducing adapter including a fittingadapted to be disposed between tubing for supplying the high pressuregas and an orifice member of the pilot burner and having an elongatedpassage therethrough, and a pressure reducing orifice carried by-thefitting in communication with the passage.

A further object of the present invention is to construct apilot burneradapter for modifying a standard pilot burner for low pressure gas ofthe inchesof water column order to operate with high pressure gas of thepounds per square inch order.

Another object of the present invention is to provide an adapter forreducing the pressure at'a pilot burner orifice sufficiently such thatthe pressure at-the pilot burner orifice corresponds to the nominalsupply pressure for an inches of water column pilot burner.

' The present invention has another object in that noise accompanyingthe reduction of pressure from a high pressure gas supply to a lowpressure required for a standard pilot burner is reduced to a minimallevel.

A further object of the present invention is to construct a pressurereducing adapter for use with a standard low pressure pilot burner suchthat the adapter may be easily installed and is composed of a minimalnumber of parts thereby reducing labor and material costs. 7

Some of the advantages of the present invention over previous attemptsto reduce the pressure at a pilot burner are that the components of theadapter of the present invention are of a simple design and may beeasily manufactured,-the adapter of the present invention may beutilized with'non-candling tab type standard pilot orifice members andthe adapter may be installed directly upstream of the pilot orificemember thereby facilitating installation thereof.

- Other objects and advantages of the present invention will becomeapparent from the following description of the preferred embodimenttaken in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING The FIGURE is a broken side elevation,partly in section, of a pilot burner adapter according to the presentinvention in combination with a main burner.

DESCRIPTION OF THE PREFERRED EMBODIMENT assembly 14. Bracket 12has anexternally threaded nipple 16 depending therefrom adapted to engage aninternally threaded nutl'8.'Nipple 16 has a cylindrical bore 20extending from an outer end22 thereof to a flared inner end 24. I

Nut l8 has a cylindrical bore 26 therethroug'h to receive a p'iece'oftubing 28 adaptedto supply gas under high pressure to 'theburn'er'assembly 14; A beveled wall 30 extends from bore 26 to an internallythreaded A wall 32 which engages nipple l6. Tubing 28 carries an annularferrule 34-adjacent an end 36 thereof; ferrule '34 having a generallytriangular configuration in cross sectionwith opposite sides 38 and. 40meeting at a flat apex.

An orifice member 42 has a curved head 44-extending slightly abovebracket 12 with a centrally disposed orifice 46 therein to permit gaseffluence to support a pilot flame. Head 44 is aligned with outer end 22of bore 20 through nipple l6 and terminates in a cylindrical wall 48which extends through bore 20 and has a flared skirt50 extendingoutwardly therefrom to engage theflared end 24 of bore 20.

' As thus far described, the pilot burner assembly may be assembled foruse with a low pressure gas supply by tightening nut 18 such thatsurface 40 of ferrule 34 seals against skirt 50 of orifice member 42 andsurface 38 engages beveled wall 30 to provide a gas seal between tubing28 and orificernernber 42. Accordingly, low pressure gas from tubing 28will escape'through orifice 46 to support the pilot flame.

An adapter for modifying the pilot burner assembly 14 as thus fardescribed for use with a high pressure gas supply isindicated generallyat 52 and includes a fitting 54 having a central cylindrical body 56with a neck 58 having an outer diameter substantially the same as theinner diameter of wall 48 of the orifice member 42. The outer surface offitting 54 around body 56 defines an outwardly extending frusto-conicalshoulder 60 adjacent neck 58, the configuration of shoulder 60corresponding to the configuration of flanged end 24 of nipple 16 andskirt 50 of orifice member 42. An annular recess 61 is formed in fitting54 within an annular collar or flange 62 depending from body 56. Flange62 has a beveled edge 63 for sealably engaging surface 40 of ferrule 34.

Projections 64 and 66 extend centrally from opposite ends of body 56 andhave grooves formed therearound by annular ribs 68 and 70, respectively.A passage 72 extends longitudinally through the center of body 56 andprojections 64 and 66 to permit gas to flow through fitting 54. A smallcup-shaped orifice member or spud 74 having a central orifice 76 ispress fitted and rolled on projections 64 and held in place by a dimpleengaging the groove formed by rib 68, and a similar small cup-shapedorifice member or spud 78 having a central orifice 80 is press fittedand rolled on projection 66 and held in place by a dimple engaging thegroove formed by rib 70. 7

ln assembly, the fitting 54 is positioned between the orifice member 42and tubing 28 such that shoulder 60, skirt 50 and flared end 24 ofnipple 16 are in tight engagement, and the tubing 28 fonns a gas sealwith fitting 54 due to engagement of surface 40 of ferrule 34 withbeveled edge 63 of flange 62 of the fitting. With nut 18 screwed ontonipple 16, the entire pilot burner assembly is tightened to provide therequired gas seal in order to prevent escaping gas.

The adapter 52 is, thus, easily assembled with a standard low pressurepilot burner in that the adapter need only be inserted between thestandard tubing and pilot orifice member. That is, the nut 18 need onlybe loosened to separate the tubing 28 from the orifice member 42 and theadapter 52 inserted therebet'ween to convert a standard low pressurepilot burner for use with a high pressure gas supply. Tubing 28desirably has end 36 chamfered to assure bottoming of the tubing inrecess 61.

Once assembled the adapter 52 operates as a pressure reducer in that thehigh pressure of the gas upstream of the adapter in tubing 28 is reducedas gas flows through orifice 80, passage 72 and orifice 76 of theadapter. Accordingly, the pressure of the gas in the chamber 82 definedbetween adapter and orifice member 42 is reduced to the nominal lowpressure required to provide a predetermined pilot flame fed by theeffluence of gas through pilot orifice 46. The combination of pressurereducing'orifices 76 and 80 and the length of passage 72 provide therequired reduction in pressure from pounds per square inch to inches ofwater column while maintaining noise at a low level.

In order to further reduce the noise level, the pressure reducingorifices of the adapter may be displaced from the longitudinal alignmentshown in the FIGURE such that the pressure reducing orifices are notaligned; and, furthermore, one or both of the pressure reducing orificescan open at an angle to the longitudinal axis of the passage 72 throughthe fitting.

The pressure in the chamber 82 between the adapter 52 and the orificemember 42 can be controlled by varying the size of the pressure reducingorifices 76 and 80. For example, when the supply pressure in tubing 28is 10 psi, the pressure in chamber 82 can be reduced to 16.9 in. ofwater column by providing pressure reducing orifices 76 and each with adiameter of 0.010 in. with pilot orifice 46 having a diameter of 0.0 l 6in.; and, with the supply pressure remaining at 10 psi, the pressure inchamber 82 can be reduced to 7.7 in. of water column by providingpressure reducing orifices 76 and 80 with diameters of 0.010 in. and0.008 in., respectively, while retaining the diameter of the pilotorifice 46 at 0.016 in.

The pilot burner adapter of the present invention may be provided withany suitable external configuration inorder to cooperate with variouspilot burners, it being of primary importance only'that the adapter havean elongated passage and a pressure reducing orifice to reduce gaspressure in the tubing prior to supply to the pilot orifice. That is,while the external configuration of fitting 54 provides an advantageousgas seal with the pilot orifice member 42 and tubing 28, otherconfigurations may be utilized dependent upon the configuration of thepilot burner support bracket and nipple and the fastening nut.

Inasmuch as the present invention is subject to many variations,modifications and changes in detail, it is intended that all matterdescribed above or shown in the accompanying drawings be interpreted asillustrative and not in a limiting sense.

What is claimed is:

l. A pressure reducing adapter for converting a low pressure pilotburner for use with a high pressure gas supply, the pilot burnerincluding an orifice member adapted to receive gas through tubing means;said adapter comprising a fitting having a central body adapted to bedisposed between the tubing means and the orifice member of the pilotburner and. having first and second projections extending from oppositeends of said central body with an elongated passage extending throughsaid central body and first and second projections, a first cup-shapedorifice member engaging said first projection .and carryinga firstpressure reducing orifice,,and a second cup-shaped orifice memberengaging said second projection and carrying a second pressure reducingorifice.

2. The pressure reducing adapter as recited in claim 1 wherein saidfirst and second pressure reducing orifices are aligned with saidpassage.

3. A pilot burner assembly for use with a high pressure gas supplycomprising tubing means adapted to supply gas under high pressure; i

pilot orifice means for establishing a pilot flame with gas under lowpressure; and

pressure reducing adapter means interconnecting said tubing means andsaid pilot orifice means including a fitting engaging said tubing meanswith a gas seal, said fitting having a central body with first andsecond projections extending from opposite ends of said central body,elongated passage means extending through said central body and firstand second projections, a first cup-shaped orifice member engaging saidfirst projection and carrying a first pressure reducing orifice, and asecond cupshaped .orifice member engaging said second projection andcarrying a second pressure reducing orifice. I 4. The pilot burnerassembly as recited in claim 3 wherein said pilot orifice means includesa member having a head with a pilot orifice therein and a cylindricalwall extending from said head and terminating at a flared skirt, andsaid central body of said fitting has a frusto-conical shoulder engagingand mating with said skirt.

5. The pilot burner assembly as recited in claim 3 wherein said fittinghas an annular recess therein receiving said tubing means and an annularflange surrounding said recess and engaging said tubing means to providea gas seal.

6. The pilot burner assembly as recited in claim 5 wherein said tubingmeans includes a ferrule disposed around the end thereof and having asurface for engaging said flange of said fitting. I

7. The pilot burner assembly as recited in claim 6 and furthercomprising a nipple having a central bore therethrough receiving saidpilot orifice member and being externally threaded, and an internallythreaded nut engaging said nipple, said fitting being disposed withinsaid nut whereby the engagement of said nut and said nipple tightenssaid pressure reducing adapter means with said tubing means and saidpilot orifice means.

8. An adapter for a pilot burner which includes a low pressure orificemeans adapted for receiving gas through tubing means, comprising afitting having a central body adapted to be disposed between thetubingmeans and the low pressure orifice means andhaving an elongated passagetherethrough, v

a first orifice member on the-fitting having a first reducing orificecommunicating from the tubing means to one end of the elongated passage,and a second orifice member on the fitting having a second reducingorifice communicating from. the other end of the elongated passage tothe low pressure orifice means,

said passage between the one and other ends having a length which withthe first and second reducing orifices provides a reduction in pressurefrom the tubing means to the low pressure. orifice means whilemaintaining noise at a low level.

9. A pressure reducing adapter for converting a low pressure pilotburner for use with a high pressure gas supply, the pilot burnerincluding a threaded-nipple, a

low pressure orifice member having a skirt for extending from thenipple, an annular'ferrule on-an end of a high pressure gas supplyingtube and a threaded nut surrounding the tube and the ferrule and adaptedto screw to the nipple and to thighten the ferrule against the skirt toseal the tube to the low pressure orifice member; said adaptercomprising a fitting adapted to be sealingly tightened by the nut andnipple between the tube and the low pressure orifice member, saidfitting having (a) a shoulder for engaging the skirt, (b) an annularflange for engaging the ferrule, and (c) an elongated passage betweenthe tube and the low pressure orifice member; and I pressure reducingorifice means carried by the fitting in communication with the passage.

10. A pressure reducing adapter as recited in claim 9 wherein saidpressure reducing orifice means includes a first pressure reducingorifice at one end of the passage, and a second pressure reducingorifice at the other end of the passage. 5 11. A pressure reducingadapter as recited in claim 9 wherein the skirt is flared,

the shoulder is frusto-conical, and

the annular flange terminates in a beveled edge for engaging theferrule.

12. A pilot burner assembly for use with a high pressure gas supplycomprising tubing means adapted to supply gas under high pressure,

low pressure orifice means for establishing a pilot flame with gas underlow pressure,

a pressure reducing adapter having a central body interconnecting thetubing means and the low pressure orifice means,

said adapter having an elongated passage extending between the tubingmeans and the low pressure orifice means, i

a first orifice member .on the adapter having a first reducing orificecommunicating from the tubing means to one end of the elongated passage,

a second orifice member on the adapter having a second reducing orificecommunicating from the other end of the elongated passage to the lowpressure orifice means, and

said passage between the one and other ends having a length which withthe first and second reducing orifices provides a reduction in pressurefrom the tubing means to the low pressure orifice means whilemaintaining noise at a low level.

sure gas supply comprising an annular ferrule on an end of a highpressure gas supplying tube;

a threaded nipple;

a low pressure orifice member having a skirt for extendingfrom thenipple;

a threaded nut surrounding the tube and the ferrule and adapted to screwto the nipple and to tighten the ferrule against the skirt to seal thetube to the low pressure orifice member;

a fitting adapted to be sealingly tightened by the nut and nipplebetween tube and the low pressure orifice member, said fitting having(a) a shoulder for engaging the skirt, (b) an annular flange forengaging the ferrule, and (c) an elongated passage between the tube andthe low pressure orifice member; and i pressure reducing orifice meanscarried by the fitting in communication with the passage.

14. A pilot burner assembly'as recited in claim 13 wherein said pressurereducing orifice means includes a first pressure reducing orifice at oneend of the passage, and a second pressure reducing orifice at the otherend of the passage.

15. A pilot burner assembly as recited in claim 13 wherein the skirt isflared,

the shoulder is frusto-conical, and

the annular flange terminates in a beveled edge for engaging theferrule.

13. A pilot burner assembly for use with a high pres-

1. A pressure reducing adapter for converting a low pressure pilotburner for use with a high pressure gas supply, the pilot burnerincluding an orifice member adapted to receive gas through tubing means;said adapter comprising a fitting having a central body adapted to bedisposed between the tubing means and the orifice member of the pilotburner and having first and second projections extending from oppositeends of said central body with an elongated passage extending throughsaid central body and first and second projections, a first cup-shapedorifice member engaging said first projection and carrying a firstpressure reducing orifice, and a second cup-shaped orifice memberengaging said second projection and carrying a second pressure reducingorifice.
 2. The pressure reducing adapter as recited in claim 1 whereinsaid first and second pressure reducing orifices are aligned with saidpassage.
 3. A pilot burner assembly for use with a high pressure gassupply comprising tubing means adapted to supply gas under highpressure; pilot orifice means for establishing a pilot flame with gasunder low pressure; and pressure reducing adapter means interconnectingsaid tubing means and said pilot orifice means including a fittingengaging said tubing means with a gas seal, said fitting having acentral body with first and second projections extending from oppositeends of said central body, elongated passage means extending throughsaid central body and first and second projections, a first cup-shapedorifice member engaging said first projection and carrying a firstpressure reducing orifice, and a second cup-shaped orifice memberengaging said second projection and carrying a second pressure reducingorifice.
 4. The pilot burner assembly as recited in claim 3 wherein saidpilot orifice means includes a member having a head with a pilot orificetherein and a cylindrical wall extending from said head and terminatingat a flared skirt, and said central body of said fitting has afrusto-conical shoulder engaging and mating with said skirt.
 5. Thepilot burner assembly as recited in claim 3 wherein said fitting has anannular recess therein receiving said tubing means and an annular flangesurrounding said recess and engaging said tubing means to provide a gasseal.
 6. The pilot burner assembly as recited in claim 5 wherein saidtubing means includes a ferrule disposed around the end thereof andhaving a surface for engaging said flange of said fitting.
 7. The pilotburner assembly as recited in claim 6 and further comprising a nipplehaving a central bore therethrough receiving said pilot orifice memberand being externally threaded, and an internally threaded nut engagingsaid nipple, said fitting being disposed within said nut whereby theengagement of said nut and said nipple tightens said pressure reducingadapter means with said tubing means and said pilot orifice means.
 8. Anadapter for a pilot burner which includes a low pressure orifice meansadapted for receiving gas through tubing means, comprising a fittinghaving a central body adapted to be disposed between the tubing meansand the low pressure orifice means and having an elongated passagetherethrough, a first orifice member on the fitting having a firstreducing orifice communicating from the tubing means to one end of theelongated passage, and a second orifice member on the fitting having asecond reducing orifice communicating from the other end of theelongated passage to the low pressure orifice means, Said passagebetween the one and other ends having a length which with the first andsecond reducing orifices provides a reduction in pressure from thetubing means to the low pressure orifice means while maintaining noiseat a low level.
 9. A pressure reducing adapter for converting a lowpressure pilot burner for use with a high pressure gas supply, the pilotburner including a threaded nipple, a low pressure orifice member havinga skirt for extending from the nipple, an annular ferrule on an end of ahigh pressure gas supplying tube and a threaded nut surrounding the tubeand the ferrule and adapted to screw to the nipple and to thighten theferrule against the skirt to seal the tube to the low pressure orificemember; said adapter comprising a fitting adapted to be sealinglytightened by the nut and nipple between the tube and the low pressureorifice member, said fitting having (a) a shoulder for engaging theskirt, (b) an annular flange for engaging the ferrule, and (c) anelongated passage between the tube and the low pressure orifice member;and pressure reducing orifice means carried by the fitting incommunication with the passage.
 10. A pressure reducing adapter asrecited in claim 9 wherein said pressure reducing orifice means includesa first pressure reducing orifice at one end of the passage, and asecond pressure reducing orifice at the other end of the passage.
 11. Apressure reducing adapter as recited in claim 9 wherein the skirt isflared, the shoulder is frusto-conical, and the annular flangeterminates in a beveled edge for engaging the ferrule.
 12. A pilotburner assembly for use with a high pressure gas supply comprisingtubing means adapted to supply gas under high pressure, low pressureorifice means for establishing a pilot flame with gas under lowpressure, a pressure reducing adapter having a central bodyinterconnecting the tubing means and the low pressure orifice means,said adapter having an elongated passage extending between the tubingmeans and the low pressure orifice means, a first orifice member on theadapter having a first reducing orifice communicating from the tubingmeans to one end of the elongated passage, a second orifice member onthe adapter having a second reducing orifice communicating from theother end of the elongated passage to the low pressure orifice means,and said passage between the one and other ends having a length whichwith the first and second reducing orifices provides a reduction inpressure from the tubing means to the low pressure orifice means whilemaintaining noise at a low level.
 13. A pilot burner assembly for usewith a high pressure gas supply comprising an annular ferrule on an endof a high pressure gas supplying tube; a threaded nipple; a low pressureorifice member having a skirt for extending from the nipple; a threadednut surrounding the tube and the ferrule and adapted to screw to thenipple and to tighten the ferrule against the skirt to seal the tube tothe low pressure orifice member; a fitting adapted to be sealinglytightened by the nut and nipple between tube and the low pressureorifice member, said fitting having (a) a shoulder for engaging theskirt, (b) an annular flange for engaging the ferrule, and (c) anelongated passage between the tube and the low pressure orifice member;and pressure reducing orifice means carried by the fitting incommunication with the passage.
 14. A pilot burner assembly as recitedin claim 13 wherein said pressure reducing orifice means includes afirst pressure reducing orifice at one end of the passage, and a secondpressure reducing orifice at the other end of the passage.
 15. A pilotburner assembly as recited in claim 13 wherein the skirt is flared, theshoulder is frusto-conical, and the annular flange terminates in abeveled edge for engaging the ferrule.